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Origin of Domesticated Plants

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10,000 years ago, before agriculture began, the world’s total human population was about 5 million. There was one person for every 25 square kilometers. Today we have more than 7 billion people, with a density of just over 25 people per square kilometer

In indigenous agriculture where the crops are grown mainly or only for sale, there develops an expanding surplus of food. The overall objective of such agricultural systems is to replace a pre-existing (natural) plant community with a cultivator-made community

“Although man did not cause variability and cannot even prevent it, he can select, preserve, and accumulate the variations given to him by the hand of nature almost in any way which he chooses; and thus can certainly produce a great result… Selection by man may be followed either methodically and intentionally, or unconsciously and unintentionally… We can further understand how it is that domestic races of plants often exhibit an abnormal character, as compared to natural species, for they have been modified not for their own benefit, but for that of man.”

The first category of germ plasm includes the native or indigenous varieties of cultivated crop plants used elsewhere in commercial agricultural production.

At present many of the major crop plants have a limited genetic base, as these have been developed through a series of selections that emphasize yield often at the expense of insect or disease resistance, environmental tolerance, multiple use, etc.